The present invention is directed towards a television tuning system which includes a circuit for preventing the loss of information stored in a memory and used by the television tuning system during its operation during power outages.
Electronic tuning systems are well known in the art. Such systems normally include a memory which stores information concerning the operating parameters of the television such as the frequency of channels which are to be tuned to, desired volume, brightness and color settings, etc. The memory also often stores other information such as the time of day, etc.
It is important to preserve the foregoing information in the case of power outages. This can be done using a permanent external memory (a battery-supplied, low consumption CMOS memory or non-volatile MNOS memory). Nevertheless, it has been shown that part of the data in the memory may be lost during the transient state between the loss of power and the return of the power.
It is a primary object of the present invention to provide a circuit arrangement designed to prevent loss of part of the data in the memory during the transient state between the loss of power and the return of the power.